Abstract: Dielectric elastomer actuator (DEA) and sensors have broad application space in national defense, medical and other fields. A large number of hydrogen bonds commonly exist inside thermoplastic polyurethanes (TPU), which severely weaken its flexibility, hampering its use for DEA. The PEG-DBA/TPU composite was prepared by using a binary plasticizer of dibutyl adipate (DBA) - polyethylene glycol (PEG). Addition of the binary plasticizer disrupted the original intermolecular hydrogen bonds of TPU, and significantly reduced the elastic modulus of the composite. Moreover, the addition also overcome the issue of DBA’s migration and the inadequate plasticizing effect of PEG as a sole plasticizer. Results demonstrated that, after loading 50wt% of DBA and 20wt% of PEG, the elastic modulus of PEG-DBA/TPU composite dramatically decreased to 0.21 MPa, only 1.4 % of elastic modulus remained (the elastic modulus of the pure TPU is 14.77 MPa). Meanwhile, dielectric constant increased from the 2.71 of DBA/TPU to the 6.02 of the PEG-DBA/TPU, increasing by 1.22 folds. Driven by 4.5 kV, DEA originated from the PEG-DBA/TPU composite exhibited stable electromechanical behaviors, its detected displacement and counted strain reached to 2.72 mm and 4.12 %, respectively increasing by 7.22 and 6.92 folds when compared to the DEA of DBA/TPU composite.